Nitinol wire /Titanium nickel alloy wire

Quick Details:

Supply Ability

Supply Ability:20 Ton/Tons per Month

Technical Parameters

Product Picture:

Titanium nickel alloy wire concept

Nickel-titanium alloy is a shape memory alloy, which is a special alloy that can automatically restore its plastic deformation to its original shape at a certain temperature. Its expansion rate is over 20%, fatigue life is up to 107 times, damping characteristics are 10 times higher than ordinary springs, and its corrosion resistance is better than the current best medical stainless steel, so it can meet the needs of various engineering and medical applications. It is a very good functional material.
In addition to its unique shape memory function, memory alloys are also resistant to wear, corrosion, high damping and superelasticity.
Characteristics of nickel-titanium alloy wire and its clinical application in the field of orthodontics Nickel-titanium alloy is widely used due to its superior superelasticity, shape memory function, corrosion resistance, and good biocompatibility and shock absorption characteristics. Orthodontic field.

Characteristics of titanium

Titanium can be subjected to various pressure processing such as forging, rolling, extrusion, stamping, etc. In principle, the equipment used for heating steel can be used for heating titanium, and the atmosphere in the furnace is required to maintain a neutral or weak oxidizing atmosphere. Heated with hydrogen.
Titanium has a higher yield ratio (σ0.2/σb), generally between 0.70 and 0.95, and the deformation resistance is large, while the elastic modulus of titanium is relatively low. Therefore, titanium is difficult to process. Pure titanium has good welding properties, and the weld strength, ductility and corrosion resistance are similar to those of the base metal. In order to prevent contamination during welding, tungsten argon shielded welding is required.
The cutting process of titanium is difficult. The main reason is that the friction coefficient of titanium is large, the thermal conductivity is poor, and the heat is mainly concentrated on the tip of the blade, so that the tip is softened quickly. At the same time, the chemical activity of titanium is high, and the temperature rises to easily adhere to the tool, resulting in bond wear. When cutting, the tool material should be properly selected to keep the tool sharp and use a good cooling process.

Phase transition and properties of Nitinol

As the name suggests, Nitinol is a binary alloy composed of nickel ions and titanium ions. Due to changes in temperature and mechanical pressure, there are two different crystal phases, namely the austenite phase and the martensite phase (Martensite). The phase transition sequence of the nickel-titanium alloy during cooling is the parent phase (austenite phase)-R phase-martensite phase. The R phase is a rhombohedral shape, and the austenite is a state in which the temperature is higher (greater than the same: the temperature at which the austenite starts to be heated), or the state at which the load is removed (external force removal Deactivation), the cube is hard. The shape is relatively stable. The martensite phase is a state in which the temperature is relatively low (less than Mf: the temperature at which martensite ends) or loading (activated by external force), hexagonal, malleable, repeatable, less stable, easier Deformation. Therefore, it is clinically determined that the phase transition temperature of Nitinol archwire has a positive guiding significance, so that clinicians can better utilize the performance of Nitinol for clinical orthodontic treatment.

Export Packing

Payment Methods:

FAQ

Q:How to get nitinol wire suitable for me?
A:Check the details and click on send us Website form or email (anber@bjhighstar.com) and tell us the specification,grade and quantity you need. We will respond to you within 2 hours and give you the best offer.

Q:What are the classification of nitinol wire?
A:bss TiNi- SS TN3 TNC..

Q:How long is your delivery time?
A:If it is in stock, we will ship it within 2 days. If it isnot in stock, the construction period is about 7-15 days.

Q:What is the payment method?
A:We support wire transfer, T/T, credit card payment, PayPal, Payoneer,Western Union.

Q:Is it possible to provide free samples?
A:Of course,We can send free samples for your test according to your needs, you only need to pay a small amount of shipping.

Production equipment

Processing workshop

Special properties of Nitinol

1. Shape memory The shape memory is that when a certain shape of the mother phase is cooled from the Af temperature to below the Mf temperature to form martensite, the martensite is deformed at a temperature below Mf and heated to below the Af temperature. With the reverse phase change, the material automatically recovers its shape at the parent phase. In fact, the shape memory effect is a thermally induced phase transition process of Nitinol.
2, superelastic (superelastic) The so-called superelasticity refers to the sample under the external force to produce a strain far greater than the elastic limit strain, the strain can automatically recover when unloading. That is, in the mother phase state, the stress-induced martensitic transformation occurs due to the applied stress, so that the alloy exhibits a mechanical behavior different from that of ordinary materials, and its elastic limit is far greater than that of ordinary materials, and the tiger is no longer observed. Gram law. Compared to shape memory characteristics, superelasticity does not involve heat. In short, superelasticity means that the stress does not increase with the increase of strain within a certain deformation range. Clinically, the orthodontic force generated by the archwire during deformation is kept constant, and no longer changes with the direction of the tooth in the direction of correction. Lost. According to the characteristics of the stress-strain curve corresponding to superelasticity, superelasticity can be divided into two types: linear superelasticity and nonlinear superelasticity. The stress-strain curve in the former has a linear relationship between stress and strain. Nonlinear superelasticity is the result of stress-induced martensitic transformation and reverse phase transformation during loading and unloading in a certain temperature range above Af. Therefore, nonlinear superelasticity is also called phase transformation pseudoelasticity. The phase-change pseudo-elasticity of Ni-Ti alloy can reach about 8%. The superelasticity of Nitinol can be changed as the conditions of the heat treatment change. When the archwire is heated above 400oC, the superelasticity begins to decrease. When the heat treatment temperature exceeds 600 ° C, the superelasticity is substantially small. According to this feature, the non-corrected area of ​​the archwire can be heat-treated to lose superelasticity, which can avoid the influence of the correction process on the teeth in the non-corrected area, and the archwire of the correction area still has good elasticity.
3. Sensitivity of temperature change in the oral cavity: The corrective force of the stainless steel wire and CoCr alloy orthodontic wire is basically not affected by the temperature inside the mouth. The orthodontic force of a superelastic nickel-titanium tooth orthodontic wire varies with the temperature of the oral cavity. When the amount of deformation is constant. As the temperature increases, the corrective force increases. On the one hand, it can accelerate the movement of the teeth, because the temperature changes in the mouth stimulate the blood flow in the stagnant part of the blood flow caused by the stagnation of the device, so that the repaired cells are fully nourished during the movement of the teeth. Maintain its vitality and normal function. On the other hand, orthodontists cannot precisely control or measure the corrective force in the oral environment.
4. Corrosion resistance: Some studies have shown that the corrosion resistance of nickel-titanium wire is similar to that of stainless steel wire.
5. Anti-toxicity: The special chemical composition of nickel-titanium shape memory alloy, that is, an atomic alloy such as nickel-titanium, containing about 50% of nickel, which is known to have carcinogenic and cancer-promoting effects. Under normal circumstances, the surface layer of titanium oxide acts as a barrier to make the Ni-Ti alloy have good biocompatibility. The surface layer of TiXOy and TixNiOy can suppress the release of Ni.
6. Mild orthodontic force: Currently used orthodontic wire for commercial use includes austenitic stainless steel wire, cobalt-chromium-nickel alloy wire, nickel-chromium alloy wire, Australian alloy wire, gold alloy wire and titanium alloy wire. The load-displacement curves for these orthodontic correction wires under tensile test and three-point bending test conditions. The unloading curve platform of Nitinol is the lowest and flattest, indicating that it provides the most durable and gentle correction.
7. Good shock absorption characteristics: The greater the vibration caused by chewing and night molars on the archwire, the greater the damage to the root and periodontal tissue. Through the results of different archwire attenuation experiments, it is found that the amplitude of stainless steel wire vibration is larger than that of superelastic nickel-titanium wire. The initial vibration amplitude of superelastic nickel-titanium arch wire is only half of that of stainless steel wire. The good vibration and shock absorption characteristics of arch wire The health of the teeth is important, and traditional archwires, such as stainless steel, have a tendency to aggravate the roots.

Free to contact us